Process for producing trehalose and sugar alcohols

Abstract

A process for producing or separating trehalose and/or sugar alcohols from hydrogenated saccharide mixtures containing trehalose and sugar alcohols selected from the group consisting of sorbitol, maltitol, and maltotriitol, which comprises the steps of subjecting hydrogenated saccharide mixtures containing trehalose and the sugar alcohols to column chromatography using strong-acid cation exchange resins, and successively eluting and collecting a trehalose-rich fraction and a sugar alcohol-rich fraction in this order.

We claim:  
     
       1. A process for producing trehalose or a sugar alcohol, which comprises the steps of: 
       providing a saccharide mixture comprising trehalose and maltose;  
       hydrogenating the resulting saccharide mixture to form a hydrogenated saccharide mixture comprising trehalose and maltitol as a sugar alcohol;  
       adjusting said hydrogenated saccharide mixture to give a concentration of at least 30 w/w %;  
       subjecting the hydrogenated saccharide mixture to column chromatography using a strong acid cation exchange resin made of a styrene/divinylbenzene polymer as a base material and which has a cross-linking of 2-8%; and  
       collecting a fraction rich in said trehalose or said sugar alcohol.  
     
     
       2. The process of claim  1 , wherein said hydrogenated saccharide mixture contains said trehalose and said sugar alcohol in respective amounts of 10-80 w/w % and 20-90 w/w %, on a dry solid basis. 
     
     
       3. The process of claim  1 , wherein said strong-acid cation exchange resin is in an alkali metal form or an alkaline-earth metal form. 
     
     
       4. The process of claim  1 , wherein said column chromatography is carried out by eluting the fraction rich in said trehalose and the fraction rich in said sugar alcohol in this order. 
     
     
       5. The process of claim  1 , which collects a fraction, as the fraction rich in said trehalose, that contains at least 90 w/w % trehalose, on a dry solid basis. 
     
     
       6. The process of claim  1 , which collects a fraction, as the fraction rich in said sugar alcohol, that contains at least 90 w/w % maltitol, on a dry solid basis. 
     
     
       7. The process of claim  1 , which further contains a step of hydrogenating a saccharide mixture containing trehalose and a reducing saccharide selected from the group consisting of glucose, maltose, and maltotriose, and which uses the resulting hydrogenated product as the hydrogenated saccharide mixture. 
     
     
       8. The process of claim  7 , wherein said saccharide mixture is one which is obtainable by contacting starch or maltose with one or more enzymes. 
     
     
       9. The process of claim  8 , wherein said enzymes are a non-reducing saccharide forming enzyme, trehalose-releasing enzyme, maltose/trehalose converting enzyme, and maltose- and trehalose-phosphorylases. 
     
     
       10. A method for separating trehalose from a sugar alcohol, which comprises the steps of: 
       providing a saccharide mixture comprising trehalose and maltose;  
       hydrogenating the resulting saccharide mixture to form a hydrogenated saccharide mixture comprising trehalose and maltitol as a sugar alcohol;  
       adjusting said hydrogenated saccharide mixture to give a concentration of at least 30 w/w %;  
       subjecting hydrogenated saccharide mixture to column chromatography using a strong-acid cation exchange resin made of a styrene/divinylbenzene polymer as a base material and which has a cross-linking of 2-8%; and  
       eluting a fraction rich in said trehalose and a fraction rich in said sugar alcohol in this order.